A typical human body has approximately 200 bones. In this textbook, only approximately 10 bones will be discussed.
Instead of focussing on individual bones, this textbook will focus primarily on segments. Nevertheless, to understand segments, it is important to know which bones belong to which segments.
| Bone name [anatomical] | Common English name | Type |
|---|---|---|
| Scapula | Shoulder OR Shoulder Blade | Bone & Segment |
| Humerus | Upper Arm | Bone & Segment |
| Radius | (None) | Bone |
| Ulna | (None) | Bone |
| Radius & Ulna | Lower Arm OR Forearm | Segment & Group |
| Humerus & Radius & Ulna | Arm OR Upper Limb | Group |
| Scapula & Humerus & Radius & Ulna & (hand and wrist bones) | Upper Limb | Group |
| Bone name [anatomical] | Common English name | Type |
|---|---|---|
| Femur | Thigh OR Upper Leg | Bone & Segment |
| Tibia | Shin | Bone |
| Fibula | (None) | Bone |
| Calcaneus | Heel | Bone |
| Tibia & Fibula | Lower Leg OR Shank | Segment & Group |
| Calcaneus & (other foot bones) | Foot* | Segment & Group |
| Femur & Tibia & Fibula | Leg | Group |
| Femur & Tibia & Fibula & Calcaneus & (other foot bones) | Lower Limb | Group |
*In Biomechanics, the foot is often modeled as a single rigid segment.
| Bone name [anatomical] | Common English name | Type |
|---|---|---|
| Vertebra* | Back bone | Bone |
| Pelvis | Hip | Bone |
| Sacrum | (None) | Bone |
| Illium | (None) | Bone |
| Illium & Sacrum | Pelvis | Segment |
| Vertebral column | Spine OR Backbone | Group |
| Trunk OR Torso | Trunk | Group & Segment* |
*"Vertebrae" is the plural of "vertebra" (i.e., one vertebra and two vertebrae).
*In Biomechanics, the trunk is often modeled as a single rigid segment, especially when modeling movements without much vertrbral column flexion (e.g. walking).
A joint allows for relative motion between bones. Joints are anatomical structures, and are usually comprised of cartilage, ligaments, tendons and other soft tissues.
The main joints considered in this textbook are the six listed in the table below.
These joints are indicated in blue font in the figures above.
| Joint name | Proximal bone | Distal bone |
|---|---|---|
| Shoulder | Scapula | Humerus |
| Elbow | Humerus | Radius & Ulna |
| Wrist | Radius & Ulna | (multiple wrist bones) |
| Hip | Sacrum | Femur |
| Knee | Femur | Tibia & Fibula |
| Ankle | Tibia & Fibula | Talus & (other foot bones) |
A typical human body contains over 600 muscles.
This textbook will consider only muscle groups, and not individual muscles.
The six main muscle groups that will be considered in this textbook are indicated below.
| Common muscle group name | Joint(s) | Main muscles [anatomical names] |
|---|---|---|
| Pectoralis | Shoulder | Pectoralis major, etc. |
| Biceps | Shoulder & Elbow | Biceps brachii, etc. |
| Triceps | Shoulder & Elbow | Triceps brachii, etc. |
| Quadriceps | Hip & Knee | Vastus, etc. |
| Hamstrings | Hip & Knee | Biceps femoris, etc. |
| Calf | Knee & Ankle | Gastrocnemius, etc. |